Door operating control for automatic elevators



Jan. 31, 1967 A, M. HALLENE ET A1.

DOOR OPERATING CONTROL FOR AUTOMATIC ELEVATORS Original Filed Feb. 14, 1963 2 Sheets-Shane?I l l TFL a 3 1FL 40h93 u 4b DOOR PEN 3 na.

fsf 25 Jan. 3l, 1967 A, M, HALLENE ETAL DOOR OPERATING CONTROL FOR AUTOMATIC ELEVATORS Original Filed Feb. `14, 1963 2 Sheets-Sheet 2 o. 3 4 c o o E| im o lllllllllllllllllllllllllllllllllllllllll .Il man? R lllllll/zs ....IIIEIII TEIIIIIST ...m IIIIIII lll||| llllllll/mlllllllll D -l I ll |||I||l| llm: iria In |-|||||f|l||m E L.; A. 4 a4 E l g c-s United States Patent O 3,301,350 DOOR OPERATING CONTROL FOR AUTOMATIC ELEVATORS Alan M. Hallene, Moline, .lohn .L Drexler, Barstow, and l Henry J. Holuba, Moline, Ill., assignors to Montgomery Elevator Company, a corporation of Delaware Continuation of application Ser. No. 258,497, Feb. 14,

1963. This application Nov. 29, 1965, Ser. No. 514,759

6 Claims. (Cl. 187-52) This application is a continuation of our application l Serial No. 258,497, filed February 14, '1963.

This invention -relates to an elevator control circuit and more specifically to a control for an automatic elevator wherein the door operation is varied depending upon the demand conditions placed upon the elevator by users thereof.

When an elevator is operated by an vattendant who controls the door operation, the number of people entering and waiting to enter or leave an elevator is quickly discernible. The attendant will not close the do-ors when it is obvious that additional passengers wish to enter or leave. The modern trend is, however, to provide automatic elevators, thus doing away with attendants, but correlated with such elimination, is the problem of providing means for actuating the doors in accordance with the loading conditions. Previously designed circuits for operating automatic elevators have met with varying degrees of success.

It is an object of this invention to provide an improved automatic elevator control circuit.

It is a further object of this invention to provide a control circuit for operating an automatic elevator in accordance with the demands placed thereon.

It is yet another object of this invention to provide in an automatic elevator system a door operation sequence depending upon the presence or absence of passengers in the pathway of the doors.

Accordingly, it is one @feature of the invention to provide a control system for an elevator car Idoor apparatus comprising means for controlling the opening, holding open and closing at a first speed of the door, a first safety device coupled t-o the controlling means actuable for preventing closing of the door when the latter is held fully open and for causing the door to close at a second reduced speed when an object enters the path of the door and the door is closing at the iirst speed, and a second safety device coupled to the controlling means actuable when the door is held open to prevent closing of the door and for opening the door when the door is closing at the first or second speeds.

It is a further feature of the invention to provide in an automatic control system for an elevator car door a timing circuit for holding the door open a first or second period of time.

It is another feature of the invention t-o provide in an automatic elevator car door control system means for closing the door at a first speed and at la second speed when an object is in the path of the door.

It is yet a further feature of the invention to provide in an automatic elevator door control system Vat least one dispatching floor position wherein a timing circuit holds the car door open a rst time period and a second time period and wherein the timing circuit is prevented from operating at said second -reduced timing period at the dispatching floor.

A preferred embodiment of the invention is illustrated in the accompanying drawings, in which:

FIGURE 1 is an across-the-line circuit diagram of the electrical control circuit for the elevator car door; and

FIGURE 2 is a key diagram of the components in FIGURE 1.

3,301,350 Patented Jan. 3l, 1967 ICC In the following discussion of the structure and operation of the disclosed embodiment, the following lettered designations will be used for the following items:

5 TFL Top floor relay. 1FL First licor relay.

EE Photoelectric relay. DOX Door safety relay. TDA Door time relay.

DO Door open signal relay.

DE Door operator pilot relay. DT Door time transfer relay. SBR Shunt brake relay.

LR Leveling relay.

DOL Dooropen limit relay.

O Door open power relay. DCL Door close limit relay. C Door close power relay. SEC Safety edge contact.

DOPB Door open push button.

MLU Magnetic leveling unit. OL Open limit switch.

CL Close limit switch.

Relay cont-acts associated with the relays are assigned the letter abbreviations of the relay, and ya number in order, as shown in the key, FIGURE 2, lwhich shows the contacts in the position assumed when the relay is deenergized.

Referring now to FIGURE 1, a pair of wires, 1, 2 is shown across which is coupled a source of potential for operating the circuit, in this instance, it is shown fas volts alternating current. A pair of leads 15, 16 are coupled to a source of 230 volts direct current for providing driving power to the door motor 18. An elevator selector mechanism (not shown) incorporates a moving brush 3 and stationary contact segments 4a and 4b. Brush 3 m-akes electrical contact with segment 4a when the elevator is positioned at the top dispatching floor, energizing 'a relay TFL, and makes electrical contact with segment 4b when the elevator is positioned at the bottom dispatching floor, energizing a relay 1FL.

A stepdown transformer 5 supplies reduced voltage to a lamp 6 which projects a beam of radiant energy across the elevator car door opening (not shown) to a photoelectric cell 7a, which is connected to an amplifier 7 coupled across leads 1, 2 containing an output relay contact 7b. When the light beam is shining on the photocell 7a, relay contact 7b is open and a relayEE is deenergized. Whenever the light beam is interrupted, output relay cont-act 7b of the photoelectric amplier 7 closes, and relay EE is energized.

The elevator car is provided with a door open pushbutton 25 for the purpose of opening the doors or causing them to remain open when .the elevator car is stopped at a floor and is further provided with a pressure-sensitive door edge which causes a contact SEC to close if an object or pers-on is st-ruck by the door edge.

An electronic timer 10 is used to determine the time interval during which the elevator doors remain open. Timer 10 is coupled across wires 1, 2 and receives power therefrom. The operating period of this portion of the circuit is -caused to time out at different time intervals by changing the circuit resistance between a pair of terminals 10a, 10b. Increasing the resistance between terminals 10a and 10b will lengthen the timing interval Whereas decreasing this value of resistance will decrease the timing interval. Electronic timer 10 initiates its timing interval when a closed circuit is established between a second pair of terminals 10c, 10d. Any interruption of the imitating circuit between terminals 10c and 10d causes the timing interval to cease and the timer to be reset. There is further provided in the timer an output relay contact e which is open before the timing interval is initated and remains open during the timing interval. Upon the eX- piration of the selected timing interval, the output relay contacts 10e closes and remains closed until the initiating circuit between terminals 10c and 10d is interrupted.

Other elevator signal circuits (not shown) cause a switch 11 to momentarily close when the car is preparing to stop for a call, and when the operation of a hall call button causes the doors to re-open at a floor where the elevator is standing.

A top terminal dispatcher (not shown) causes a c-ontact 12 to open when the elevator receives the start down signal at the top terminal, and ya bottom terminal dispatcher (not shown) causes a contact 13 to open when the elevator receives the start up signal at the bottom terminal. In addition, a contact 14 associated with the elevator shunt brake contactor (not shown) is open when the elevator is not in motion and is closed when the elevator is running.

A further contact MLU-1 is associated with a magnetic leveling unit (not shown) on the elevator car and closes as the elevator approaches within a few inches of the'floor where it has been required to stop. Contact MLU-1 remains closed while the elevator remains at the floor and reopens as the car leaves the floor.

The elevator door operating mechanism (not shown) c-ontains an open limit switch, OL, and a close limit switch, CL. The open limit switch contacts separate when the door reaches the fully open position, and the close limit switch contacts open when the door is closed.

The door operating mechanism is driven by a direct current motor including a shunt held winding 17 and an armature 18. A speed regulating resistance 19 is utilized to adjust the normal speed of the elevator door operation. A second regulating resistor 20 is utilized to adjust the slow speed of the door operator motor.

When the elevator car is running through the shaft, shunt brake relay SBR is energized through a switch 14 associated with the brake contactor (not shown) and door open limit relay DOL is energized through the now closed door open limit switch OL.

As the elevator is signaled to stop `for a call, switch 11 closes momentarily and energizes door open signal relay DO through contacts SBR-1 and TDA1. Relay DO becomes self-holding through contacts DO-2, SBR-1 `and TDA-1. Door time transfer relay DT is energized through contacts DO-4 and DCL-1 and becomes selfholding through contacts DO-4, DT-, and EE-S.

Relay contact DT-1 closes to connect resistor 8 between terminals 10a and 10b of the electronic timer 10. Relay contact DT-2 opens to disconnect resistor 9 from between terminals 10a and 10b of the electronic timer 10.

As the elevator approaches within `a few inches of the oor where it will stop, magnetic leveling unit contact MLU-1 closes and energizes leveling relay LR which closes contact LR-l, and door operator pilot relay DE is energized through LR-l and DO-3. In addition, relay contact DE-2 closes and 'door open power relay O is energized through contacts C-2, DE-Z yand OL.

Relay contacts O-2 and O-3 close to apply voltage across the door operator motor armature 18, and the door operator motor operates in the opening direction at normal speed. As the doors begin to open, door close limit switch CL closes and door close limit relay DCL is energized. The car stops level with the floor land shunt brake contactor switch 14 opens to cause relay SBR to become deenergized. Relay contact SBR-1 opens causing relay DO to become self-holding through contacts TDA-1 and DO-2. Relay contact SBR-3 closes and relay DE becomes self-holding through contacts SBR-3, DE-l and DOL-2.

When the doors are fully open, door open limit switch OL opens deenergizing door open power rel-ay O and door open limit relay DOL. Relay contacts O-2 and CII 0 3 open to disconnect voltage 4from the door operator motor armature 18 and the door motor stops.

Contact DOL-1 closes and the initating circuit between terminals 10c and 10d is established through DOL-1, EE-Z and DO-l, and electronic timer 10 begins to time out for a rst timing interval determined by the value of resistance of resistor 8. Relay contact DOL-2 opens and the holding circuit -for relay DE, including contacts SBR-3, DE-l and DOL-2 is broken.

Relay DE does not become deenergized, but remains energized through contacts LR-1 and DO-3.

Assuming thereafter that no passengers enter or leave the car so that the photoelectric beam is not interrupted, no further relay operations occur immediately.

At the end of the first timing interval, measured from the time when the doors reach the fully open position, the uninterrupted closure of the electronic timer 10, initiating circuit between terminals 10c and 10d, will cause electronic timer contact 10e to close. Door time relay TDA is energized, contact TDA-1 opens, and relay DO is deenergized. Relay contact DO-2 also opens to interrupt the self-holding circuit for relay DO. Relay contact DO-l opens to interrupt the initiating circuit between terminals ltc and 10d of electronic timer 10; timer contact 10e immediately opens, relay TDA is deenergized, and timer 10 is reset.

Relay contacts DO-3 and DO-4 open causing relays DE and DT to become deenergized. Relay contact DEL-3 closes to energize door close power relay C, contact DT-1 opens to disconnect resistor 8 and relay contact DT-Z closes to connect resistor 9 across terminals 10a and 10b of the electronic timer 10.

When relay C becomes energized, relay contacts C-3 and C-S close to apply voltage to the door operator motor armature 18. The door operator motor operates in the closing -direction at normal speed.

As the doors start closing and leave the fully open position, door open limit switch OL closes, land relay DOL is energized. When the doors are fully closed, door close limit switch CL opens, and relays C and DCL are deenergized. Relay contacts C-3 and C-S open to disconnect voltage from the door `operator motor armature 18 and the door operator motor stops.

Operating the pressure-sensitive safety edge contact SEC or the door open push button 25 while the doors are open will cause the doors to remain open. When contact SEC or door open push button 25 closes, door safety relay DOX is energized and relay DO becomes energized through contacts SBR-2 fand DOX-1. Power is supplied to relay DE through LR-l and DO3, and contact DE-3 opens to prevent relay C from lbecoming energized and closing power cannot be applied to the door operator motor and the doors rem-ain open.

If the pressure-sensitive door edge and the door open push button are released be-fore the expiration of the rst time interval, the doors will remain open until expiration of the rst time interval and then close. With both the safety edge contact, SEC, and door open push button 25 released, relay DOX is deenergized. When the first time interval expires, electronic timer contact 10e closes. Relay TDA picks up or is energized, and contact TDA-1 opens. vRelay DO drops out or is deenergized, and contact DO-Z opens breaking relay DOs self-holding cir-cuit. Contact DO-1 opens and causes timer 10 to reset and reopen contact 10e. Relay TDA drops out, lbut relay DO cannot pick up :again when contact TDA-1 closes because contact DO-2 is open. Door operator pilot relay DE drops out when DO-3 opens, and door close power relay C picks up when DE-3 closes. Thus, door closing power is applied to the door motor.

If the safety edge contact, SEC, or door open push Ibutton 25 is released after the expiration of the rst time interval, the doors close immediately upon such release. With either the safety edge or door open push button being operated with the doors open, relay DOX is tacts SBR-2 and DOX-1. Since relay DO cannot drop out, contact DO-l cannot open to interrupt the initiating circuit for electronic timer between terminals 10c and 10d. Contact 10e remains closed, relay TDA remains picked up, and contact TDA-1 remains open. As soon as both the pressure-sensitive door edge and door open push button are released, relay DOX will dr-op out and contact DOX-1 will open. Relay DO will drop out immediately -because contact TDA-1 has been opened. When relay DO drops out, relay DE drops out, and relay C picks up as explained previously, and the doors close immediately.

I-f the safety edge contact, SEC, or door open push button 2S is operated while the -doors are closing, the doors reopen lfully. Operating either of these two energizes relay DOX, and contact DOX-1 closes to energize relay DO through contact SBR-2 which becomes selfholding through contact TDA-1 and DO-2. Relay contact DO-3 closes to energize relay DE through contact LR-l and becomes self-holding through contacts SBR-3, DE-l and DOL*2. Relay contact DE-S opens to deenergize relay C. Contact DE2 closes to energize relay O through contact C-2 and open limit switch OL. When relay O is energized, the door operator motor operates in the opening direction at normal speed until the doors are fully open. v

Interruption of the photoelectric unit beam has different results under diiterent conditions which are as follows.

Interruption of the photoelectric unit beam the rst time at a oor other than the dispatching floors reduces the door open time Afrom a rst time interval to a second, shorter interval. Interrupting the photobeam minal, relay DT is retained energized by a circuit through causes photoelectric amplifier output relay contact 7b to close, thus energizing relay EE. Contact EE-S opens, and relay` DT is deenergized through the interruption of its self-holding circuit including contacts DO-4, DT-3 and EE3. Contact EE-Z opens to interrupt the initiating circuit between terminals 10c and 10d of electronic timer 10, land timerk 10 resets instantaneously. Contact DT-l opens to disconnect the rst time interval resistor 8 [from the timing range terminals 10a and 10b of electronic timer 10. Contact DT'-2 closes connecting the second time interval resistor 9 to the timing range terminals 10a and 10b of electronic timer 10. When the photobeam is cleared, contact 7b reopens, relay EE is deenergized, contact EE-Z closes to reestablish the initiating circuit between terminals 10c and 10d of electronic timer 10, and the electronic timer begins timing out the shorter time interval.

Each subsequent operation of the photoelectric beam at a floor other than the ldispatching iloors extends the door open time for the second time interval measured from the time of restoration of the beam. Each time the beam is subsequently interrupted, contact 7b closes to energize relay EE. Contact EZB-2 opens to interrupt the timer initiating circuit between terminals 10c and 10d Yand the electronic timer resets instantaneously. When second time interval. When the car is at the top dispatching iloor, brush 3 makes contact with segment 4a, causing TFL to energize. When the car is at the bottom dispatching terminal, Ibrush 3 makes contact with segment 4b, causing relay 1FL to energize. As the car approaches `a dispatching terminal, relay DT is energized through contacts DO-4 and DCL-1 and becomes self-- holding through contacts DO-4, DT-3 and EE-3 just as at any intermediate floor. When the car is adjacent the dispatching floor level, either relay TFL or 1FL is energized.

At the top dispatching terminal, relay4 contact TFL-1 closes to ffurther retain relay DT energized through contact 12. At the bottom dispatching terminal, contact 1FL-1 closes to further retain relay DT energizedI through contact 13. Thus, the interruption of the photobeam and the corresponding opening of contact EES does not cause relay DT to become deenergized as long as contact 12 remains closed when the car is at the top dispatching terminal or as long as contact 13 remains closed when the car is at the bottom dispatching terminal. If relay DT does not become deenergized, contact DT-1 remains closed causing the irst time interval resistor 8 to be connected to the electronic timers timing range terminals 10a and 10b. Contact 12 remains closed until the dispatching time interval expires at the top dispatching terminal and contact 13 remains closed until the dispatching time interval expires at the bottom dispatching terminal. Each interruption of the photobeam extends the door open time for the first time interval measured from the time of restoration of the beam.

If the doors are fully open at a dispatching iloor after the dispatch interval has elapsed, each interruption of the photoelectric unit beam extends the door open time by` the second time interval measured rfrom the restoration of the beam. When the car is at the top dispatching tercontacts TFL-1 and 12 and by a circuit through contacts DO-4, DT-3 and EE-3. When the dispatching interval elapses |at the top terminal, contact 12 opens andl The rst time that contact EE-3 opens, relay DT is deenergized; resistor 8 is disconnected by the opening of contact DT1, and resistor 9 is connected by the closing of contact DT-Z across the timing range terminals 10aa and 10b of electronic timer 10. A similar operation holds true when the car is at the bottom dispatching terminal, wherein contact 13 opens when the -dispatching interval elapses at the bottom dispatching terminal.

If the photocell beam is interrupted at any oor while the doors are closing, the nate of door closing is reduced to the lowest speed 1for which the door operator is adjusted, and the doors continue to close at the slow speed. When the beam is restored the doors resume normal closing speed, and may again slow down if the beam is re-interrupted. When the -doors are closing and their position is somewhere between the fully open and fully closed positions, the relays DOL, DCL, LR and C are in ian energized condition. All other relays are deenergized at this time. When the beam is interrupted, contact 7b closes and relay EE is energized. Contact C-1 is open and, therefore, the closing of contact EE-l cannot cause relay DOX to become energized. Since relay DOX cannot become energized, relay DO remains deenergized, and relay DE will remain deenergized. If relay DE cannot become energized, relay C will remain energized. Relay contact EE-4 closes, causing slow speed adjustment resistor 20 to be connected across the door operator motor armature 18 through contact C-4. When resistor 20 is connected across armature 18, a greater amount of current is caused to flow through resistor 19 which increases the voltage drop across resistor 19 and decreases the voltage across armature 18. With less voltage applied to the door motor armature, the speed-of door operating motor is reduced. The doors -will continue to close at slow speed as long as the photobeam is interrupted as contact EE-4 remains closed. When the beam is restored, contact 7b opens :and relay EE is deenergized. Contact EE`4 opens to disconnect resistor 20 from across armature 18 and normal armat-ure voltage is applied to the door operator motor with the result that the doors resume their normal closing speed. Each subsequent operation of the photobeam causes contact EE-4 to close and place resistor 20 lacross armature 18 to reduce the door closing speed as long as the photobeam is interrupted.

Interruption of the photoelectric beam when the doors are fully open causes Contact 7b to close and disables the door closing operation until the beam is reestablished. Relay EE becomes energized through 7b and contact EE-l closes to energize relay DOX through contact C-l. Contact EE-2 opens to interrupt the initiating circuit for electronic timer fbetween its terminals 10c and 10d, thus preventing timer 10 from timing out and closing contact 10e. Relay DO becomes energized through SBR-Z and DOX-1 and becomes self-holding through contacts TDA-1 and DO-Z. Relay DE is energized through contacts LR-l and DO-3, and contact DE-3 opens to prevent relay'C from becoming energized. If relay C is not energized, door closing power cannot be applied to the door operator motor armature, and the doors remain open. When the photobeamis reestablished, contact 7b opens to deenergize relay EE. Contact EE-l opens to deenergize relay DOX and contact EE-Z closes to establish the initiating circuit between terminals 10c and 10d for electronic timer 10 through contacts DOL-1 and DO-1. (Timer 10 begins to time out.) Contact DOX-1 opens, but relay DO remains energized through TDA-1 and DO-2. When timer 10 times out, contact 10e closes to energize relay TDA. Contact TDA-1 opens to deenergize relay DO and conta-ct DO-l opens to interrupt the initiating circuit between terminals 10c and 10d of electronic timer 10 and the timer resets instantaneously. Contact 10e reopens and relay TDA drops out to cause contact TDA-1 to close, but relay DO cannot pick up again because contacts DO-2 and DOX-1 are now open. Contact DO-3 opens to deenergize relay DE and contact DE-3 closes to energize rela; C through contact O-1 and switch CL. When relay vC is energized, door closing power is applied to the door operator motorand the doors close at normal speed.

The pressure-sensitive door safety edge contact SEC or door open push button 25 may operate in the usual fashion whether the doors are closing at regular speed or at slow speed. Asdescribed above, operation of safety edge contact SEC or door open push button 25 causes relay DOX to become energized to remove closing power from the door operator motor. 'In addition, contact DE-Z closes to energize relay O to apply opening power to the door operator motor.

There is no circumstance under which the fully open doors may start to close if the pressure-sensitive door edge or the door open button is actuated, or if the photoelectric beam is interrupted.

We claim:

1. In a control system for the door of an elevator which serves a plurality of floors, apparatus comprising: n means for opening and closing said door; a timer responsive to opening movement of said door to initiate a timing period and to generate a signal actuating said door closing means at the end of said period, said timer having two timing circuits with different timing periods; means for selecting the longer of said timing periods on opening said door; a door time transfer circuit for selecting the shorter of said timing periods; means for sensing passage ofa person through said open door; and means responsive to said sensing means for actuating said transfer circuit to select the shorter of the timing periods and reduce the door open time upon passage of a person through the door.

2. The elevator door control system of claim 1 wherein said elevator serves a terminal floor an-d including means responsive to the presence of said elevator car at said terminal floor to maintain selection of said longer timing circuit; a source of elevator dispatching signals; and means responsive to receipt of a dispatching signal for modifying said door timer transfer circuit to respond to passage of a person through said door actuating the door timer transfer circuit to select the shorter of the timing periods.

3. The -control system of claim 1 including further means responsive to said sensing means for reducing the door closing rate while an object is in the open door.

4. The elevator control system of claim 1 wherein said door time transfer circuit includes a relay having normally open and normally closed contacts and said timer has two timing circuits, one connected with the timer through the normally open contacts and the other connected with the timer through a normally closed contact of said door time transfer relay, the means responsive to the sensing means effecting a reversal of condition of the relay and said contacts.

5. The control system ofvclaim 4 wherein a circuit for said relay is completed energizing the relay upon arrival of the car at a floor, closing the normally open contacts and wherein the timing circuit for the longer timing interval is connected with the timer through the normally open contacts, said relay having a holding -circuit including a contact responsive to said sensing means and opened on passage of a person through said door, deenergizing said relay and connecting the timing circuit for the shorter period with the timer through the normally closed contacts.

6. The control system of claim S including a terminal holding circuit connected in parallel with the holding circuit for said relay, said terminal holding circuit including contacts opened upon receipt of a dispatch signal from a source.

References Cited by the Examiner l UNITED STATES PATENTS 2,900,521 s/1959 Eames.

3,050,154 s/1962 Bruns t 137-52 X 3,080,947 3/1963 stone 1s7h52 3,092,209 6/1963 Burgy 1237-52y SAMUEL F. COLEMAN. Primary Examiner. 

1. IN A CONTROL SYSTEM FOR THE DOOR OF AN ELEVATOR WHICH SERVES A PLURALITY OF FLOORS, APPARATUS COMPRISING: MEANS FOR OPENING AND CLOSING SAID DOOR; A TIMER RESPONSIVE TO OPENING MOVEMENT OF SAID DOOR TO INITIATE A TIMING PERIOD AND TO GENERATE A SIGNAL ACTUATING SAID DOOR CLOSING MEANS AT THE END OF SAID PERIOD, SAID TIMER HAVING TWO TIMING CIRCUITS WITH DIFFERENT TIMING PERIODS; MEANS FOR SELECTING THE LONGER OF SAID TIMING PERIODS ON OPENING SAID DOOR; A DOOR TIME TRANSFER CIRCUIT FOR SELECTING THE SHORTER OF SAID TIMING PERIODS; MEANS FOR SENSING PASSAGE OF A PERSON THROUGH SAID OPEN DOOR; AND MEANS RESPONSIVE TO SAID SENSING MEANS FOR ACTUATING SAID TRANSFER CIRCUIT TO SELECT THE SHORTER OF THE TIMING PERIODS AND REDUCE THE DOOR OPEN TIME UPON PASSAGE OF A PERSON THROUGH THE DOOR. 